【作者】 李云霞；

【导师】 王增才；

【作者基本信息】 山东大学 ， 车辆工程， 2016， 博士

【摘要】 胶带输送机软起动装置普遍存在价格昂贵、维护成本高的问题,低成本软起动装置成为市场需求的方向。重型电控机械式自动变速器(AMT)以其传递扭矩大、成本低在重型车辆中得到了广泛应用,将其用作胶带输送机的软起动装置是AMT应用领域的创新,具有巨大的市场价值。本文在国家自然科学基金《放顶煤支架尾梁振动信号分析法检测顶煤放落程度研究》(N0.51174126)的资助下,对AMT软起动胶带输送机的起步过程控制和换挡过程控制进行了深入研究。论文的主要工作及研究成果如下：(1)建立AMT软起动胶带输送机系统的力学模型。根据AMT软起动胶带输送机系统的动力传递原理,建立了AMT传动系统动力学方程。通过建立胶带输送机力学模型,分析了输送带不打滑条件、物料不滑动条件和输送带的运动方程。通过建立离合器、TB制动器、电磁阀的力学模型,分析了AMT气动系统的时滞性。所建AMT系统的动力学模型能够描述胶带输送机的动力传递过程,体现AMT气动系统的时滞性,为后续起步和换挡控制方法研究奠定基础。(2)研究AMT软起动胶带输送机的软起动加速度控制曲线。通过对常用五种胶带输送机软起动曲线特性的优缺点分析,提出了适合AMT软起动胶带输送机的梯形和直角梯形软起动加速度曲线。利用AMESim软件建立AMT软起动胶带输送机的动态仿真模型,对比分析了梯形和直角梯形加速度起动曲线下AMT软起动胶带输送机的动态响应,从胶带输送机输送带速度、加速度、冲击度和张力参数的变化来看两种软起动曲线可满足软起动要求。(3)研究起步过程负载参数估计方法。针对负载参数对换挡过程控制的影响,提出了一种基于起步过程半接合点的负载阻力矩估计和基于递推最小二乘法的负载惯量递推估计方法。根据起步过程半接合点的位置信息和离合器扭矩位移特性,得到负载阻力矩估计值。根据加速阶段离合器位移和输出轴转速,构建负载惯量估计模型,采用递推最小二乘算法对负载惯量估计模型进行在线估计。(4)设计AMT软起动胶带输送机起步过程离合器接合各阶段的控制器。根据软起动目标要求,给出了软起动品质评价指标和控制需求。通过对起步过程的分析,确定各阶段的控制任务,分别设计了离合器空行程阶段、克服阻力阶段、加速阶段的控制器。为控制起步瞬间输送带冲击度和减小滑摩功损耗,克服阻力阶段采用基于抛物线位移曲线的数据驱动CFDL-MFAC控制算法进行了离合器位移跟踪。为便于AMT控制,将加速阶段对输送带加速度和冲击度的控制等效为对输出轴角加速度和冲击度的控制,采用冲击度补偿模糊PID控制算法对直角梯形加速度控制曲线进行跟踪。(5)研究无同步器式AMT同步换挡控制策略。提出了基于输入轴制动的同步转速差升挡策略和基于输入轴等待输出轴降速的同步降挡策略。通过对同步升挡和同步降挡的理论分析,设计了输入轴控制量算法,根据执行机构的滞后性,以同步转速差条件作为换挡时刻的依据。根据TB制动特性,采用基于控制限幅的PD控制算法对TB制动器进行控制,用于跟踪由输入轴期望转速算法得到的输入轴降速曲线规律,直至达到同步转速差要求。(6)设计AMT软起动胶带输送机换挡过程离合器接合各阶段的控制器。根据软起动目标要求,给出了换挡品质评价指标和控制需求。为控制输送带冲击度,克服阻力阶段采用基于抛物线位移曲线的数据驱动CFDL-MFAC控制算法进行了离合器位移跟踪。以负载参数识别为基础,在加速阶段采用基于接合位置预测与修正的模糊PID控制方法对输出轴直角梯形角加速度控制曲线进行了跟踪。(7)设计AMT软起动胶带输送机的电子控制系统。给出了AMT电子控制系统总体控制方案及底层、中间层和上层软件的设计框架,为试验提供软、硬件支持。(8)验证AMT软起动胶带输送机的控制方案。设计了离合器接合与分离特性试验、离合器扭矩位移特性试验、TB制动特性试验、起步过程控制试验、换挡过程控制试验,验证了AMT软起动胶带输送机起步过程和换挡过程控制方案的可行性。更多还原

【Abstract】 The common soft starters of the belt conveyor are expensive and have high maintenance costs. So soft starter with lower cost is becoming the demand of the market. Heavy AMT has been widely used in heavy vehicles because of its large torque and low cost. It is an innovation to use AMT as the soft starter of belt conveyor in the application field of AMT which has huge market value.Supported by the National Natural Science Foundation of China (Grant No. 51174126), the starting process control and shifting process control of AMT softly starting belt conveyor are deeply researched. The main work and contributions are summarized as follows:(1) Mechanical model has been established for AMT softly starting belt conveyor. Dynamic equations of AMT’s transmission system are established according to the power transmission principle of AMT softly starting belt conveyor. The non-slip conditions for the belt and the materials are analyzed with the help of the mechanical model. The motion equations of the belt are also analyzed. The models of the clutch, the transmission brake and the solenoid valve are established which are used to analyze the time delay characteristics of AMT pneumatic system. The mechanical model of AMT system can describe the power transmission process of the belt conveyor and reflect the time delay characteristics of AMT pneumatic system which lays a foundation for the following research of starting process and shifting control method.(2) Starting acceleration control curves of AMT softly starting belt conveyor have been researched. The trapezoidal and orthogonal trapezoidal soft starting acceleration curves are proposed which suit AMT softly starting belt conveyor through analyzing the advantages and disadvantages of common five soft starting curves. AMESim is used to establish the dynamic simulation model of AMT softly starting belt conveyor. Comparative analysis is made between the dynamic responses of AMT softly starting belt conveyor with trapezoidal soft starting acceleration curves and that with orthogonal trapezoidal soft starting acceleration curves. The two soft starting curves can meet the requirements of soft starting according to the velocity, acceleration, jerk and tension of the belt.(3) Estimation method of load parameters has been researched during starting process. According to the influence of load parameters on shifting process control, an estimation method of load resistance torque based on semi joint of the starting process is proposed. A recursive estimation method of load inertia based on recursive least square algorithm is also proposed. According to the location of the semi joint of the starting process and the clutch characteristic of torque and displacement, the load resistance torque estimation is obtained. According to the clutch displacement and the speed of the output shaft during acceleration stage, the estimation model of load inertia is established, and the load inertia is estimated on line with the help of the recursive least square algorithm.(4) Controllers of the clutch engagement stages during starting process have been designed for AMT softly starting belt conveyor. According to the requirements of soft starting, the evaluation indicators of starting quality and control requirements are given. Control tasks for each stage are determined through analyzing the starting process. Controllers for different stages are designed separately including the empty stroke stage, resistance stage and acceleration stage. In order to decrease the belt jerk and sliding friction loss while starting, CFDL-MFAC control algorithm based on parabolic displacement curve is used to track the clutch displacement during resistance stage. For the convenience of AMT control, the control of belt acceleration and jerk is replaced by the control of output shaft’s angular acceleration and jerk during acceleration stage. A fuzzy PID control algorithm with jerk compensation is used to track the orthogonal trapezoidal acceleration curve.(5) Synchronous shifting control strategy for AMT without synchronizer has been researched. Synchronous rotational speed difference upshift control strategy is proposed which is based on the braking of the input shaft. Synchronous downshift control strategy is also proposed which makes the input shaft always wait for the output shaft to decelerate. Control algorithm of the input shaft is designed through theoretical analysis of synchronous upshift and synchronous downshift. The synchronous rotational speed difference is taken as the basis to decide the shifting time because of actuator’s hysteresis. According to transmission brake’s property, a kind of PD control algorithm with limiting the amplitude is used to control transmission brake. The rule of the input shaft’s deceleration curve is tracked which is got through the desired speed of the input shaft until the required synchronous rotational speed difference is reached.(6) Controllers of the clutch engagement stages during shifting process have been designed for AMT softly starting belt conveyor. According to the requirements of soft start, the evaluation indicators of shifting quality and control requirements are given. In order to control the belt jerk, CFDL-MFAC control algorithm based on parabolic displacement curve is used to track the clutch displacement during resistance stage. Based on the load parameters identification, a fuzzy PID control method based on engagement position prediction and correction is used to track the orthogonal trapezoidal angular acceleration control curve of the output shaft during acceleration stage.(7) Electronic control system has been designed for AMT softly starting belt conveyor. The overall scheme of AMT’s electronic control system and the software design frameworks of the bottom layer, the middle layer and the upper layer are given which provides software and hardware support for the test.(8) The control schemes of AMT softly starting belt conveyor have been verified. Several experiments have been designed including clutch engagement and disengagement characteristic experiment, clutch’s characteristic experiment of torque and displacement, transmission braking characteristic experiment, control experiment of starting process and control experiment of shifting process. It is verified that the control schemes of starting process and shifting process of AMT softly starting belt conveyor are feasible.更多还原